On the classification of automorphisms of trees


  • Samuel Coskey Boise State University
  • Kyle Beserra University of North Texas




We identify the complexity of the classification problem for automorphisms of a given countable regularly branching tree up to conjugacy. We consider both the rooted and unrooted cases. Additionally, we calculate the complexity of the conjugacy problem in the case of automorphisms of several nonregularly branching trees.



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